Tsunamis A tsunami is an ocean wave often caused by earthquakes on the ocean floor; these waves typically have long wavelengths, ranging from 150 to 1000 km. Imagine a tsunami traveling across the Pacific Ocean, which is the deepest ocean in the world, with an average depth of about 4000 m. Explain why the shallow-water velocity equation (Exercise 75) applies to tsunamis even though the actual depth of the water is large. What does the shallow-water equation say about the speed of a tsunami in the Pacific Ocean (use d = 4000 m)?
Ch. 7 - Logarithmic, Exponential Functions, and Hyperbolic Functions
모든 교과서
Briggs 3rd Edition
Ch. 7 - Logarithmic, Exponential Functions, and Hyperbolic Functions
문제 7.3.12
Briggs 3rd Edition
Ch. 7 - Logarithmic, Exponential Functions, and Hyperbolic Functions
문제 7.3.127장, 문제 7.3.12
11–15. Identities Prove each identity using the definitions of the hyperbolic functions.
tanh(−x) = −tanh x
검증된 단계별 안내1
Step 1: Recall the definition of the hyperbolic tangent function: .
Step 2: Substitute into the definition of . This gives: .
Step 3: Factor out from the numerator of the fraction: .
Step 4: Recognize that the numerator is the negative of the numerator in the definition of . Thus, .
Step 5: Conclude that the identity is proven using the definition of hyperbolic functions.

비슷한 문제에 대한 검증된 영상 답변:
이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
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주요 개념
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Hyperbolic Functions
Hyperbolic functions are analogs of trigonometric functions but are based on hyperbolas rather than circles. The primary hyperbolic functions include sinh(x), cosh(x), and tanh(x), which are defined as sinh(x) = (e^x - e^(-x))/2, cosh(x) = (e^x + e^(-x))/2, and tanh(x) = sinh(x)/cosh(x). Understanding these definitions is crucial for proving identities involving hyperbolic functions.
추천 영상:
Asymptotes of Hyperbolas
Odd and Even Functions
An odd function is defined by the property f(-x) = -f(x), while an even function satisfies f(-x) = f(x). The hyperbolic tangent function, tanh(x), is an odd function, which means that tanh(-x) = -tanh(x). This property is essential for proving identities involving tanh, as it allows for simplifications when substituting negative arguments.
추천 영상:
Properties of Functions
Proof Techniques in Calculus
Proof techniques in calculus often involve direct substitution, algebraic manipulation, and the application of definitions. To prove identities like tanh(−x) = −tanh x, one typically starts with the left-hand side, applies the definition of tanh, and uses properties of exponents and odd functions to arrive at the right-hand side. Mastery of these techniques is vital for successfully demonstrating mathematical identities.
추천 영상:
Fundamental Theorem of Calculus Part 1
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∫ cosh 2x dx
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